A new list of the nation's top urban arts districts includes one you might not expect: downtown Oakland.

That's the verdict of ArtPlace, a national nonprofit that makes grants to arts-related efforts and on Monday released its selection of the 12 neighborhoods "most successfully combining art, artists and other creatives ... to make vibrant places." The criteria included such "vibrancy indicators" as cell phone activity and the presence of museums, dance studios and musical instrument stores.

In Oakland's case, the report emphasized the diverse scenes represented by everything from the venerable Everett & Jones barbecue to the popular Art Murmur on the first Friday of every month and the Crucible, an industrial facility noted for its "unique cyberpunk Burning Man-related crowd."

While there's a mention of the city's entrenched poverty, ArtPlace concludes "Oakland is experiencing a new energy that hasn't been seen since the 1940s."

Nor was the other city by the bay left out. Along with such hot spots as Brooklyn's Gowanus and the Pearl District in Portland, the top 12 includes San Francisco's "artistic breeding ground" - the Mission District.

Here's something you probably don't know: San Francisco has approximately 54,000 street signs. And as you might have noticed, some are becoming more polite.

The change involves the use of upper- and lower-case lettering for street names, a departure from the city's practice until now. It's a world where Haight is no longer HAIGHT, and FELL doth fall to Fell.

This being San Francisco, I've received calls and e-mails about the shift from such dismayed readers as Alan Hanagriff, who isn't alone in preferring "a cleaner look with all of the letters in capital."

But don't blame local politicians for the new look. California last year adopted "uniform traffic control devices," federal standards that run a daunting 1,402 pages. Tucked into the section on street name signs is a statement that research "supports the enhanced legibility of mixed-case legends in comparison to all upper-case legends." Ah, the world of bureaucratic divination.

As with all sweeping legal edicts, this one includes a caveat of sorts.

To keep the new rules from being a burden on local governments, changes are required only when a sign needs to be replaced. For the record, a typical sign costs $250 and has a 12-year life span.

So if you're the betting sort, time to make a wager. When will the final ALL-CAPS SIGN come down? And at which corner will an Ess Eff tradition bite the dust?

Design and cultural issues related to downtown San Francisco's privately owned public spaces are the subject of what should be a lively panel Tuesday evening.

Rounding out the panel are two veterans from New York City. One is landscape architect Thomas Balsley, who has designed two dozen such plazas. The other, Jerold Kayden, wrote the book on how not all oases are created equal: "Privately Owned Public Space: The New York City Experience" analyzed all 500-plus spaces in that city with an eye to which ones enhance their surroundings and which ones were functionally off-limits to the public at large.

The panel begins at 6 p.m. on Tuesday at the SPUR Urban Center, 654 Mission St.; for more information and to make reservations go to www.spur.org. Full disclosure: I'm moderating, but I promise to let the panel do the talking.

Incidentally, the Planning Department's interactive map to all spaces created in tandem with downtown commercial projects is now online at popos.sfplanning.org. Put it to good use.

Finally, an appreciative farewell to Ada Louise Huxtable - the first architecture critic at the New York Times and the first recipient of the Pulitzer Prize for criticism. She died on Sunday at the age of 91.

Along with The Chronicle's Allan Temko, Mrs. Huxtable defined why newspapers should pay attention to the buildings and landscapes of our cities. Her final piece appeared last month in the Wall Street Journal, and it is impossible to convey the length of the spirited shadow that she cast.